Can't close your account if you've logged in with SSO

[lampholder]

This is probably true for all password-authed actions (change password, delete devices, delete key backup?, close account).

[turt2live]

This is matrix-org/synapse#5667

[softvision-sergiulogigan]

I think my situation fits this already opened issue:

I used to work with Mozilla, and during that time, I was logged into Riot using my SSO credentials.
Now, my SSO is disabled, and I cannot deactivate my account (it asks me to use SSO to prove my identity).

[t3chguy]

Now, my SSO is disabled, and I cannot deactivate my account (it asks me to use SSO to prove my identity).

There is nothing that can be done about this on Riot's end, it just passes on the server's request for verifying your identity.
You should contact your server admins to resolve this issue.

This issue is actually solved as per matrix-org/synapse#5667 being closed